This SAE Recommended Practice is intended for use in testing and
evaluating the approximate performance of enginedriven cooling
fans. This performance would include flow, pressure, and power.
This flow and pressure information is used to estimate the engine
cooling performance. This power consumption is used to estimate net
engine power per SAE J1349. The procedure also provides a general
description of equipment necessary to measure the approximate fan
performance.

The test conditions in the procedure generally will not match
those of the installation for which cooling and fuel consumption
information is desired. The performance of a given fan depends on
the geometric details of the installation, including the shroud and
its clearance. These details should be duplicated in the test setup
if accurate performance measurement is expected. The performance at
a given air density and speed also depend on the volumetric flow
rate, or the pressure rise across the fan, since these two
parameters are mutually dependent. These parameters depend on the
pressure drop across the radiator core and the ram pressure due to
vehicle motion. For these reasons, the test procedure should be
recognized as providing only an approximate measure of installed
fan performance.

Although the test procedure is based on running the fan with a
motoring dynamometer, the actual installation can be used as a test
fixture if an accurate torque meter is available. In this case, the
same qualifications discussed apply. Finally, for the effect of a
fan clutch in reducing fan use and power consumption, which is not
a part of this procedure, refer to SAE J1342.

Purpose

This document provides a recommended test procedure for
measuring and comparing the performance of fans over a range of
pressure and speeds. The resulting performance data are intended
for predicting the cooling performance and fuel consumption of
engines using these fans, and in comparing one fan versus
another.